We will probe the viral gene pool seeking relationships between DNA conformation, biological activity and facility to bind specific proteins. Proteins of dual or multiple function in viral DNA synthesis and maturation and the regulation of host gene function probably exist in this system. Mutation and mapping of the phage genome will enable us to eventually complete the genetic map of phi 29 and search for bacterial genes essential for specific stages in viral biosynthesis. In vitro studies of DNA-protein interaction in concert with viral transfection are contemplated. BIBLIOGRAPHIC REFERENCES: Hagen, E. W., and Anderson, D. L. 1975. In situ lysis of phi 29- and SPO1-infected Bacillus subtilis. J. Virology 15:217-200. Reilly, B. E., Tosi, M. E., and Anderson, D. L. 1975. Genetic analysis of bacteriophage phi 29 of Bacillus subtilis: mapping of the cistrons coding for structural proteins. J. Virology 16:1010-1016.